A cryogenic vacuum system typically includes at least one cryogenic vacuum pump (cryopump) and at least one compressor for supplying compressed helium to the cryopump. The system also often includes other components such as roughing pumps, waterpumps, turbopumps, chillers, valves and gauges. Together, these components operate to provide cryogenic cooling to a broader system, such as a cluster tool for semiconductor processing.
A cluster tool includes a tool host controller providing top-level control over all systems within the cluster tool. The tool includes a series of processing chambers for performing various semiconductor-fabrication processes such as wafer etching, chemical or plasma vapor deposition, oxidation, sintering, and annealing. These processes often are performed in separate chambers, each of which includes a cryopump of the cryogenic vacuum system.
In addition to the cryopumps, a conventional vacuum system typically includes a network interface terminal which communicates in the RS-232 protocol with the tool host controller and also communicates in the BitBus protocol to the network of cryopumps within the system. Other vacuum system components, such as a roughing pump, compressor, and gate valve, are typically coupled with the tool host controller to allow the tool host controller to issue commands for controlling the operation of these components.